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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

The impact of food and nutrient intake on bone from childhood to early adulthood

Vatanparast, Hassanali 22 August 2006
Development of peak bone mass during childhood to early adulthood has been considered as a major determinate of risk of fracture and osteoporosis later in life. The purpose of this project was to determine the impact of food and nutrient intake on bone from childhood to early adulthood using mixed longitudinal data from the University of Saskatchewan Pediatric Bone Mineral Accrual Study (PBMAS). <p>To determine the role of consumption of milk products and vegetable and fruit on the total body-bone mineral content (TB-BMC) accrual in boys and girls from childhood to late adolescence, seven-year longitudinal data were used. Using a multilevel modeling statistical approach containing major biological and environmental factors, vegetables and fruit intake, calcium intake and physical activity were significant independent environmental predictors of TB-BMC in boys. <p>Change in the pattern of beverage intake of adolescents as a major component of nutrition transition has aroused health concerns such as obesity, tooth decay, and inadequate bone accrual. Beverage consumption and its relationship with calcium intake of grade 9 students from 1991 to 2004 was evaluated. Percent contribution of milk to total beverage intake was significantly decreased in boys and girls. A significant negative association between milk intake and consumption of non-carbonated soft drinks was observed in both genders. In girls only, a significant negative trend in calcium intake was observed over time. <p>Milk products, specifically fluid milk, were the major source of dietary calcium from childhood to early adulthood in both genders. There was a substitution of fluid milk by cheese, a decrease in vegetable and fruit intake, and the low intake of vitamin D in young adults, specifically females. <p>The effect of food and nutrient intake, measured at young adult age and previously in peri-adolescence, on bone mass was investigated. In males, the intake of calcium from peri-adolescence to early adulthood was sustained, whereas in females, there was a significant decrease. Height, weight, protein intake, physical activity and gender were the significant predictors of bone measures only in young adults who had consistent calcium intake from peri-adolescence. Collectively, the results of this study present the bone protective nutrients and food groups from childhood to early adulthood in our cohort. The food choices and dietary habits of the cohort change by age, but not in the favour of bones, with females more at risk. To prevent risk of osteoporosis, there should be promotion of a healthy dietary plan, not a single food group or nutrient, accompanied with an adequate level of physical activity.
52

The impact of food and nutrient intake on bone from childhood to early adulthood

Vatanparast, Hassanali 22 August 2006 (has links)
Development of peak bone mass during childhood to early adulthood has been considered as a major determinate of risk of fracture and osteoporosis later in life. The purpose of this project was to determine the impact of food and nutrient intake on bone from childhood to early adulthood using mixed longitudinal data from the University of Saskatchewan Pediatric Bone Mineral Accrual Study (PBMAS). <p>To determine the role of consumption of milk products and vegetable and fruit on the total body-bone mineral content (TB-BMC) accrual in boys and girls from childhood to late adolescence, seven-year longitudinal data were used. Using a multilevel modeling statistical approach containing major biological and environmental factors, vegetables and fruit intake, calcium intake and physical activity were significant independent environmental predictors of TB-BMC in boys. <p>Change in the pattern of beverage intake of adolescents as a major component of nutrition transition has aroused health concerns such as obesity, tooth decay, and inadequate bone accrual. Beverage consumption and its relationship with calcium intake of grade 9 students from 1991 to 2004 was evaluated. Percent contribution of milk to total beverage intake was significantly decreased in boys and girls. A significant negative association between milk intake and consumption of non-carbonated soft drinks was observed in both genders. In girls only, a significant negative trend in calcium intake was observed over time. <p>Milk products, specifically fluid milk, were the major source of dietary calcium from childhood to early adulthood in both genders. There was a substitution of fluid milk by cheese, a decrease in vegetable and fruit intake, and the low intake of vitamin D in young adults, specifically females. <p>The effect of food and nutrient intake, measured at young adult age and previously in peri-adolescence, on bone mass was investigated. In males, the intake of calcium from peri-adolescence to early adulthood was sustained, whereas in females, there was a significant decrease. Height, weight, protein intake, physical activity and gender were the significant predictors of bone measures only in young adults who had consistent calcium intake from peri-adolescence. Collectively, the results of this study present the bone protective nutrients and food groups from childhood to early adulthood in our cohort. The food choices and dietary habits of the cohort change by age, but not in the favour of bones, with females more at risk. To prevent risk of osteoporosis, there should be promotion of a healthy dietary plan, not a single food group or nutrient, accompanied with an adequate level of physical activity.
53

Removal of nutrients from lake water by intergral vertical flow and subsurface flow constructed wetlands

Wu, Pei-shuan 29 July 2008 (has links)
Constructed wetlands (CWs) utilize the natural mechanisms in wetlands to remove pollutants by physical, chemical and biological processes. CWs are one of the ecological engineering methods to purity water quality and has been experimented to assess their capabilities to remove nutrients from eutrophic water bodies of lakes and reserviors. This study was carried out to compare the removal of nutrients between vegetated and unvegetated CWs. The vertical flow bed was placed in the upstream, while the horizontal subsurface flow bed was set in the downstream. Cannaceae was selected to plant in the vegetated CWs. Two kinds of hydraulic retention time (HRT), 3 days and 7 days, were applied and compared with each other in this study. The experimental results show that no significantly difference between vegetated and unvegetated systems. The removal efficiencies of SS, BOD, NH3-N, TP are measure equal to about 80%, 75%, 80% and 65%, respectively, while the removal efficiencies of TN, OP, and COD were reached about 50% and larger. Both of the two systems show high efficiencies for nutrient removal. In the comparison between the two kinds of HRT¡¦s, the HRT controlled at 3 days presented higher removal efficiencies than that controlled at 7 days.
54

The role of copepods and heterotrophic dinoflagellates in the production of dissolved organic matter and inorganic nutrients /

Saba, Grace Kathleen, January 2009 (has links)
Thesis (Ph. D.)--College of William and Mary. / Vita. Includes bibliographical references. Also available online.
55

The role of intracellular storage products in biological nutrient removal /

Zeng, Raymond Jianxiong. January 2002 (has links) (PDF)
Thesis (Ph. D.)--University of Queensland, 2002. / Includes bibliographical references.
56

Phytoplanktonic primary production along a eutrophic, turbid estuarine gradient (Colne estuary, UK)

Kocum, Esra January 1998 (has links)
No description available.
57

Phosphorus limitation in Alton Water reservoir

Perkins, Rupert Gordon January 1999 (has links)
No description available.
58

The effect of intermittent flow on the growth and development of NFT lettuce /

Bedasie, Simon. January 1985 (has links)
No description available.
59

Effects of nutrient enrichment on alkaline phosphatase activity and nitrogen fixation potential in stream periphyton

Lang, David A. King, Ryan Steven, January 2007 (has links)
Thesis (M.S.)--Baylor University, 2007. / Includes bibliographical references (p. 62-73).
60

Effects of shelf-life on phytonutrient composition in stored non-alcoholic beer

Majoni, Sandra. January 2006 (has links) (PDF)
Thesis PlanA (M.S.)--University of Wisconsin--Stout, 2006. / Includes bibliographical references.

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